Concept

Nonce (cryptographie)

Publications associées (12)

On Succinct Non-interactive Arguments in Relativized Worlds

Succinct non-interactive arguments of knowledge (SNARKs) are cryptographic proofs with strong efficiency properties. Applications of SNARKs often involve proving computations that include the SNARK verifier, a technique called recursive composition. Unfort ...

SPRINGER INTERNATIONAL PUBLISHING AG2022

Can Caesar Beat Galois?

Serge Vaudenay, Damian Vizár

The Competition for Authenticated Encryption: Security, Applicability and Robustness (CAESAR) has as its official goal to “identify a portfolio of authenticated ciphers that offer advantages over [the Galois-Counter Mode with AES]” and are suitable for wid ...

2018

ClaimChain: Improving the Security and Privacy of In-band Key Distribution for Messaging

Carmela González Troncoso, Wouter Lueks, Bogdan Kulynych

The social demand for email end-to-end encryption is barely supported by mainstream service providers. Autocrypt is a new community -driven open specification for e-mail encryption that attempts to respond to this demand. In Autocrypt the encryption keys a ...

ACM2018

Provably Secure Authenticated Encryption

Damian Vizár

Authenticated Encryption (AE) is a symmetric key cryptographic primitive that ensures confidentiality and authenticity of processed messages at the same time. The research of AE as a primitive in its own right started in 2000. The security goals of AE wer ...

EPFL2018

Secure Contactless Payment

Serge Vaudenay, Handan Kilinç Alper

A contactless payment lets a card holder execute payment without any interaction (e.g., entering PIN or signing) between the terminal and the card holder. Even though the security is the first priority in a payment system, the formal security model of cont ...

2018

Arithmetic and geometric structures in cryptography

Benjamin Pierre Charles Wesolowski

We explore a few algebraic and geometric structures, through certain questions posed by modern cryptography. We focus on the cases of discrete logarithms in finite fields of small characteristic, the structure of isogeny graphs of ordinary abelian varietie ...

EPFL2018

Linking Online Misuse-Resistant Authenticated Encryption and Blockwise Attack Models

Damian Vizár

Real-world applications of authenticated encryption often require the encryption to be computable online, e.g. to compute the ith block of ciphertext after having processed the first i blocks of plaintext. A significant line of research was dedicated to id ...

2017

Authenticated Encryption with Variable Stretch

Serge Vaudenay, Damian Vizár, Reza Reyhanitabar

In conventional authenticated-encryption (AE) schemes, the ciphertext expansion, a.k.a.stretch or tag length, is a constant or a parameter of the scheme that must be fixed per key. However, using variable-length tags per key can be desirable in practice or ...

Springer-Verlag Berlin2016

Online Authenticated-Encryption and its Nonce-Reuse Misuse-Resistance

Damian Vizár, Reza Reyhanitabar

A definition of online authenticated-encryption (OAE), call it OAE1, was given by Fleischmann, Forler, and Lucks (2012). It has become a popular definitional target because, despite allowing encryption to be online, security is supposed to be maintained ev ...

Springer2015

On Selecting the Nonce Length in Distance-Bounding Protocols

Serge Vaudenay, Christos Dimitrakakis, Aikaterini Mitrokotsa

Distance-bounding protocols form a family of challenge-response authentication protocols that have been introduced to thwart relay attacks. They enable a verifier to authenticate and to establish an upper bound on the physical distance to an untrusted prov ...

Oxford University Press2013

Obfuscation for Cryptographic Purposes

Martijn Stam

Loosely speaking, an obfuscation O of a function f should satisfy two requirements: firstly, using O, it should be possible to evaluate f; secondly, O should not reveal anything about f that cannot be learnt from oracle access to f alone. Several definitio ...

Springer Verlag2010

Passive-Only Key Recovery Attacks on RC4

Serge Vaudenay, Martin Vuagnoux

We present several weaknesses in the key scheduling algorithm of RC4 when the secret key contains an initialization vector - a cryptographic scheme typically used by the WEP and WPA protocols to protect IEEE 802.11 wireless communications. First, we show h ...

Springer2007